Aphasia is an impairment of language ability. This class of language disorder ranges from having difficulty remembering words to being completely unable to speak, read, or write. Aphasia disorders usually develop quickly as a result of head injury or stroke, but can develop slowly from a brain tumor, infection, or dementia, or can be a learning disability such as dysnomia. The area and extent of brain damage determine the type of aphasia and its symptoms. Aphasia types include Broca's aphasia, non-fluent aphasia, motor aphasia, expressive aphasia, receptive aphasia, global aphasia and many others (see)...